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Accurate structural descriptor enabled screening for nitrogen and oxygen vacancy codoped TiO_(2) with a large bandgap narrowing

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Journal of Materials Science & Technology 2022年第27期122卷 84-90页

作者： Kangyu Zhang lichang yin Gang liu Hui-Ming Cheng Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Physics and Electronic Information Huaibei Normal UniversityHuaibei 235000China

Nitrogen(N)doping has been widely adopted to improve the light absorption of TiO_(2).However,the newly introduced N-2p states are largely localized thus barely overlap with O-2p states in the valence band of TiO_(2),resulting in a shoulder-like absorption *** realize an apparent overlap between N-2p and O-2p states,charge compensation between N^(3-)and O^(2-)via electron transfer from oxygen vacancies(VO)to N dopants is one possible *** verify this,in numerous doping configurations of N/VO-codoped anatase TiO_(2),we identified two types of VOposition independent N-dopant spatial orderings by efficient screening enabled with a newly designed structural *** with others,these two types of the N-dopant spatial orderings are highly beneficial for charge compensation to produce an apparent overlap between N-2p and O-2p states,therefore achieving a large bandgap ***,the two types of the N-dopant spatial orderings can also be generalized to N/VO-codoped rutile TiO_(2)for bandgap narrowing.

关键词： Structural descriptor TiO_(2) Bandgap narrowing Doping Machine learning Density functional theory

Constructing CdSe QDs modified porous g-C_(3)N_(4)heterostructures for visible light photocatalytic hydrogen production

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Journal of Materials Science & Technology 2021年第36期95卷 167-171页

作者： Zheng Zhang Yuyang Kang li-chang yin Ping Niu Chao Zhen Runze Chen Xiangdong Kang Fayu Wu Gang liu School of Material and Metallurgy University of Science and Technology LiaoningAnshan 114051China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China

Constructing heterostructures with narrow-band-gap semiconductors is a promising strategy to extend light absorption range of graphitic carbon nitride(g-C_(3)N_(4))and simultaneously promote charge separation for its photocatalytic activity ***,its highly localized electronic states of g-C_(3)N_(4)hinder photo-carrier migration through bulk towards heterostructure interfaces,resulting in low charge carrier separation efficiency of solid bulk g-C_(3)N_(4)-based ***,porous g-C_(3)N_(4)(PCN)material with greatly shortened migration distance of photo-carriers from bulk to surface was used as an effective substrate to host Cd Se quantum dots to construct type II heterostructure of Cd Se/PCN for photocatalytic hydrogen *** homogeneous modification of the Cd Se quantum dots throughout the whole bulk of PCN together with proper band alignments between Cd Se and PCN enables the effective separation of photo-generated charge carriers in the ***,the Cd Se/PCN heterostructure photocatalyst gives the greatly enhanced photocatalytic hydrogen production activity of192.3μmol h^(-1),which is 4.4 and 8.1 times that of Cd Se and PCN,*** work provides a feasible strategy to construct carbon nitride-based heterostructure photocatalysts for boosting visible light driven water splitting performance.

关键词： Porous g-C_(3)N_(4) CdSe QDs Heterostructure Photocatalytic water splitting

Directed segregation in compartmentalized bi-disperse granular gas

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Chinese Physics B 2012年第1期21卷 284-288页

作者： Sajjad Hussain Shah li yin-chang Cui Fei-Fei Zhang Qi Hou Mei-ying Physics Department Beijing Institute of TechnologyBeijing 100081China Institute of Physics Chinese Academy of SciencesBeijing 100190China

A bi-disperse granular gas in an asymmetrical two-compartment system is studied experimentally. The presence of asymmetry within the range of our experimental parameters results in a directed segregated state and a directed clustering state. This deterministic system does not depend on the initial conditions. A modified flux model based on Lohse＇s flux model for bi-disperse granular gases is derived. The modified flux model explains qualitatively the experimental results.

关键词： granular matter segregation nonlinear dynamics

Irregular Oscillation of Bi-disperse Granular Gas in Cyclic Three Compartments

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Chinese Physics Letters 2012年第3期29卷 128-131页

作者： Sajjad Hussain Shah li yin-chang CUI Fei-Fei ZHANG Qi Pierre Evesque HOU Mei-ying Department of Physics Beijing Institute of TechnologyBeijing 100081 Institute of Physics Chinese Academy of SciencesBeijing 100190 Lab MSSMat EcoleCentrale de Paris92295 Châtenay-MalabryFrance

A 3-D molecular dynamics simulation of a bi-disperse vibro-fluidized granular gas in a cyclic three-compartment cell is performed.A cluster of particles is randomly found in one of the ***'s flux model is modified to incorporate inelastic particle-boundary *** model predicts that periodically there is clustering in each *** is then found that if the model is further modified to incorporate Gaussian white noise,it correctly predicts the non-sequential clustering behavior confirming that there is no chaotic behavior.

关键词： behavior disperse incorporate

Adaptive Modulation with Channel Estimation in High-Speed Packet-Based OFDM Communication Systems

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The Journal of China Universities of Posts and Telecommunications 2004年第z1期11卷 76-82页

作者： HOU Xiao-lin WU Jun-li yin chang-chuan YUE Guang-xin School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China

In this paper, adaptive modulation with channel estimation in high-speed packet-based Orthogonal Frequency Division Multiplexing (OFDM) communication systems for beyond 3G are discussed. Different adaptive modulation and channel estimation methods are presented and compared, then those methods suitable for our intended application are chosen. Conclusions can be drawn from computer simulations that with proper selection of packet length and subband width, wide subband adaptive modulation with Least Square plus Discrete-time Fourier Transform (LS-DFT) channel estimation can give an acceptable performance with low complexity for channel with low Doppler shift and small path delay. Otherwise, narrow subband or subcarrier adaptive modulation together with LS-DFT plus Decision Directed (LS-DFT-DD) must be used.

关键词： OFDM adaptive modulation channel estimation beyond 3G

High-Spin Structure in Odd-Odd 160Lu Nucleus

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Chinese Physics Letters 2012年第6期29卷 98-101页

作者： WANG lie-lin LU Jing-Bin YANG Dong MA Ke-Yan ZHOU yin-Hang yin li-chang WU Xiao-Guang WEN Shu-Xian li Guang-Sheng YANG Chun-Xiang College of Physics Jilin UniversityChangchun 130023 Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory Southwest University of Science and TechnologyMianyang 621010 Institute of Nuclear Physics and Chemistry Chinese Academy of Engineering PhysicsMianyang 621900 China Institute of Atomic Energy Beijing 102413

The high-spin states of 160Lu are populated by the fusion-evaporation reaction 144Sm(19F,3n)160 Lu at beam energies of 90 and 106 Me V.A new level scheme of 160Lu is established.A possible isomeric state based on the πh11/2 (0) υh9/2 configuration is *** new decoupled band with the configuration of πd3/2[411]1/2^(+) (0)υi13/2[660] 1/2^(+) is established,and the configurations of these similar decoupled bands in the neighboring odd-odd 162-166 Lu nuclei are suggested.A positive parity coupled band is assigned as the πd5/2[402]5/2^(+)(0)υi13/2[660]1 /2^(+)configuration.

关键词： configuration configuration neighboring

单壁碳纳米管改变手性外延生长的密度泛函理论研究（英文）

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新型炭材料 2016年第5期31卷 525-531页

作者：谌为李峰刘畅尹利长中国科学院金属研究所沈阳材料科学国家(联合)实验室辽宁沈阳110016

采用密度泛函理论计算系统研究了单壁碳纳米管（Single-walled carbon nanotube,SWCNT）改变手性外延生长（手性指数从（n,m）变化到（n±Δ,m±Δ）,其中Δ=1和2）的热力学过程。结果表明,碳管手性变化后外延生长在热力学上都需要吸收... 详细信息

采用密度泛函理论计算系统研究了单壁碳纳米管（Single-walled carbon nanotube,SWCNT）改变手性外延生长（手性指数从（n,m）变化到（n±Δ,m±Δ）,其中Δ=1和2）的热力学过程。结果表明,碳管手性变化后外延生长在热力学上都需要吸收能量,其所需吸收的能量随着管径的减小线性减小。在Δ=1的情况下,由于近扶手椅型碳管改变手性时,所引入的5～7元环对与管轴的夹角比近锯齿型碳管更大,导致5～7元环对的形成能增加,使得管径相同的近扶手椅型碳管比近锯齿型碳管在改变手性生长时需要吸收更多的能量。在Δ=2的情况下,发现只有当两个必须引入的5～7元环对相互毗邻,手性改变的外延生长所需能量最小,预测其为实验上最易于实现的碳管手性指数由（n,m）变化到（n±Δ,m±Δ）的外延生长模式。这些理论研究结果有助于深入理解SWCNTs手性变化后外延生长的热力学行为,可为基于外延生长可控制备单一手性SWCNTs提供理论依据。

关键词：单壁碳纳米管手性变化 5~7缺陷外延生长密度泛函理论

Observation of Low-Lying and linking Transitions in ^(124)Cs

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Chinese Physics Letters 2001年第1期18卷 21-23页

作者： LU Jing-Bin liU Yun-Zuo yin li-chang ZHANG Fan WU Xiao-Guang WEN Shu-Xian li Guang-Sheng YANG Chun-Xiang Department of Physics Jilin UniversityChangchun 130023 China Institute of Atomic Energy Beijing 102413

The level states of the nucleus ^(124)Cs have been populated through the ^(116)Sn(^(11) B,3n)reaction at a beam energy of 45MeV,provided by the HI-13 tandem accelerator of the China Institute of Atomic Energy.A number of low-lying states are *** level states in theπh_(11/2)νg_(7/2) side band are extended down to lower spin by one *** level energies and spins in the rotational bands are determined through the establishment of various connections,which confirm the spin assignment of the yrast band in ^(124)Cs based on excitation energy *** is revealed that with the present spin assignment,theπh_(11/2)νg_(7/2) side band shows signature inversion at low-spin region and the inversion occurs at a spin of about 16h.

关键词： assignment Transition

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王国维的“古史新证”与“古史辨运动”

四川师范大学学报（社会科学版） 2021年第3期48卷 170-179页

作者：李长银山东大学儒学高等研究院儒家文明省部共建协同创新中心

在中国近代古史学上,“疑古派”与“考古派”虽然在研究目的与方法上存在较大的差异,但并不能因此而否定二者之间的学术关联。作为“考古派”的开山大师,王国维向来对“疑古派”及“古史辨运动”持批评态度,主张“与其打倒什么,不如建... 详细信息

在中国近代古史学上,“疑古派”与“考古派”虽然在研究目的与方法上存在较大的差异,但并不能因此而否定二者之间的学术关联。作为“考古派”的开山大师,王国维向来对“疑古派”及“古史辨运动”持批评态度,主张“与其打倒什么,不如建立什么”。不过,心理事实不等于历史事实,其苦心孤诣取得的诸多考古研究成果,如《殷卜辞中所见先公先王考》、《殷卜辞中所见先公先王续考》、《殷周制度论》、《汉代文字考》、《桐乡徐氏印谱序》等,均被以顾颉刚为代表的“疑古派”“拿来”论证了自家的“疑古”之说。因此,王国维可被视为“古史辨运动”中无法忽视的一位“被动参与者”。这一学术事实的考定,可为相关学术研究工作提供若干思考和启迪。

关键词：王国维 “古史新证” “古史辨运动” 中国近代古史学顾颉刚钱玄同杨宽